$20$ women together can complete a work in $16$ days. $16$ men together can complete the same work in $15$ days. The ratio of the working capacity of a man to that of a woman is

$4$ men or $6$ women or $10$ children can paint a house in $5$ days. The painting is given to a couple (a man and a woman) and their $5$ sons. They finish the job in (in days):

$A$ can do a work in $10 \text{ days}$ and $B$ in $20 \text{ days}$. If they work together on it for $5 \text{ days}$,then the fraction of the work that is left is:

$A$ does $\frac{2}{5}$ of a work in $9$ days. Then $B$ joined him and they together completed the remaining work in $6$ days. $B$ alone can finish the whole work in (in days):

$A$ can do a certain work in the same time in which $B$ and $C$ together can do it. If $A$ and $B$ together could do it in $10 \text{ days}$ and $C$ alone in $50 \text{ days}$,then $B$ alone could do it in (in $\text{days}$):

If $10$ men or $18$ boys can do a work in $15$ days,then the number of days required by $15$ men and $33$ boys to do twice the work is